A platoon guide is a position, but not a rank in the United States Army and Marine Corps.

In an infantry platoon

Platoon

A platoon is a military unit typically composed of two to four sections or squads and containing 16 to 50 soldiers. Platoons are organized into a company, which typically consists of three, four or five platoons. A platoon is typically the smallest military unit led by a commissioned officer—the...

 the platoon guide is a non commissioned officer who acts as an assistant platoon sergeant

Platoon Sergeant

In many militaries, a platoon sergeant is the senior enlisted member of a platoon, who advises and supports the platoon's commanding officer in leading the unit.-Singapore:...

. The platoon guide is responsible for ensuring the platoon is supplied with ammunition and rations.

In a basic training

Basic Training

Basic Training may refer to:* Basic Training, a 1971 American documentary directed by Frederick Wiseman* Basic Training , an American sex comedy* Recruit training...

 unit, the platoon guide is the senior recruit in the platoon chosen by his or her Drill Instructor

Drill instructor

A drill instructor is a non-commissioned officer or Staff Non-Commissioned Officer in the armed forces or police forces with specific duties that vary by country. In the U.S. armed forces, they are assigned the duty of indoctrinating new recruits entering the military into the customs and...

 as a liaision between the Drill Instructor and the platoon and the recruit leadership of the platoon.. The platoon guide also carries the platoon guidon.